This invention relates to a fastener which has a high engaging force, which generates fluffing only very slightly and which is prevented from being lowered in engaging force after repeated attachment and detachment. It also relates to an absorbent article using such a fastener.
Heretofore, fasteners of the type comprising a male material and a female material of a mechanical fastener have been used in various fields including the field of absorbent articles such as disposable diapers because of the reasons that repeated attachment and detachment is possible and they have a proper engaging force. In general, as a female material of such a mechanical fastener, those fabrics, which can be obtained by knitting many fibers into a loop pattern or an arch pattern on a base seat, are used. However, since such fabrics exhibit a comparatively stiff feel, the base material is deteriorated in feel when they are adhered to the base material. Moreover, since the manufacturing process is complicated, productivity becomes low and cost becomes high.
In order to obviate such problems, there have been made several proposals of a nonwoven fabric composed by forming a loop on its single surface side by way of needle punch, span bond, span race or heat contraction (Japanese Patent Laid-Open Publication Nos. 06-33359, 07-171011, 07-313213, etc.). However, those proposed nonwoven fabrics are, when compared with knitted fabrics, generally low in degree of freedom (movability of fibers) and hardly wrapped with male materials. Accordingly, it is difficult to obtain sufficient engaging force. There has also been proposed a female material using spun bond or the like, in which strength in joining point between fibers is reduced in order to enhance the degree of freedom. Although such a female material has sufficient engaging force, it has such shortcomings that fluffing is heavily generated, lowering of engaging force occurrable when repeated detachment is made is significant, and the problems of productivity and cost are not yet completely solved.
It is, therefore, an object of the present invention to provide a fastener comprising a mechanical fastener which has a high engaging force and which generates fluffing only very slightly, and an absorbent article using the same.
It is another object of the present invention to provide a fastener comprising a mechanical fastener in which an engaging force is not lowered when repeated attachment and detachment is made, and an absorbent article using the same.
It is a further object of the present invention to provide a fastener comprising a mechanical fastener which is high in productivity and which can be manufactured at a low cost, and an absorbent article using the same.
The inventors of the present invention have found out that the generation of fluffing can be prevented by using a specific nonwoven fabric as a female material of a mechanical fastener and that an engaging force can be enhanced by using the female material in combination with a male material which is provided, at a specific density, with hooks having a specific configuration, thus enabling to achieve the above objects.
The present invention have been accomplished based on the above finding. According to the present invention, there is provided, in order to achieve the above objects, a fastener comprising a male material, having many hooks, of a mechanical fastener and a female material, made of nonwoven fabric, of the mechanical fastener, the male material engaging the female material, wherein many hooks in the male material have a density of 100 to 1000 pieces/cm2, a height of 300 to 1500 xcexcm and a width of 100 to 500 xcexcm.
According to another version of the present invention, there is provided, in order to achieve the above objects, an absorbent article comprising a liquid-permeable topsheet, a liquid-impermeable backsheet and a liquid-retentive absorbent core interposed between the topsheet and the backsheet, a fastening tape for the use of securement being arranged at each of opposing left and right side edge regions of a back-side zone, a landing tape capable of being secured to the fastening tape being arranged at a stomach-side zone, wherein a male material, having many hooks, of a mechanical fastener is used as the fastening tape, the many hooks having a density of 100 to 1000 pieces/cm2, a height of 300 to 1500 xcexcm and a width of 100 to 500 xcexcm, and a female material, made of nonwoven fabric, of the mechanical fastener is used as the landing tape or otherwise, the female material is used as the fastening tape and the male material is used as the landing tape.